The present invention relates to a system and a method for more efficiently deploying and retrieving large external loads from an aircraft, such as a helicopter.
Currently, the U.S. Navy and the Japanese Maritime Self Defense force deploy and retrieve airborne mine counter measures (AMCM) equipment using a system 10 such as that shown in FIG. 1. The system 10 includes a tow boom 12, a winch 14, a davit 16, a cradle 18, a modified aircraft ramp 20 capable of moving from an up and closed position to a 90 degree (vertically down) open position, and an aperture guard 19. Airborne mine counter measure deployment and retrieval operations are performed as follows. The tow boom 12 is moved from its center line stowed position to a side stow position. The winch cable 22 is unwound from the winch 14 aft to the davit sheave 24. The davit sheave cable retainer is opened and the cable 22 is laid on the sheave 24 and locked in place by closing the davit cable retainer. The cable 22 is then run to and attached to the towed body 28. The towed body 28 is unstrapped from its transport cradle 18. The davit 16 is rotated aft from its stowed forward position while the winch 14 is then activated, lifting the towed body 28 from its cradle 18. At the same time, the ramp 20 is lowered to further increase the clearance between the cradle 18 and the towed body 28. Continuous rotation aft of the davit 16 is maintained as the ramp 20 is now also lowered until the towed body 28 fully clears the ramp 20 and the cradle 18. The towed body 28 is then further lowered until it enters the water by a synchronous operation of the winch 14 and the davit 16. A tow ball is secured to the tow cable 22. The tow boom 12 is rotated to the aircraft center line and lowered over the tow cable 22 and the tow ball. The tow cable 22 is played off the winch 14 to trap the tow ball in the tow hook 34. A guillotine is placed over the tow cable 22 and secured to the aft facing end of the tow boom tow hook 34. The aircraft is now ready to begin tow operations. Towed body retrieval is the reverse of this procedure, with the additional crew task of using a manually held pole to stabilize and correct the attitude of the towed body 28 as it approaches the aircraft.
This prior art system is very inefficient and can have a large weight impact on the basic aircraft. This prior art system also is very labor intensive and has high risk tasks associated with it. Still further, this prior art system requires extensive fuselage modifications.
Accordingly, it is an object of the present invention to provide a system and a method for deploying and retrieving large external loads from an aircraft such as a helicopter.
It is a further object of the present invention to provide a system and a method as above which is simpler to use.
It is still a further object of the present invention to provide a system as above which is self-contained and modular in nature.
It is yet a further object of the present invention to provide a deployment and retrieval system which can be integrated into an existing aircraft structure with minimum structural modifications.
The foregoing objects are attained by the deployment and retrieval system and method of the present invention.
In accordance with the present invention, a system for deploying and retrieving an external load from an aircraft, such as a helicopter, broadly comprises a support frame, a winch connected to the support frame, a tow cable wound around the winch, which tow cable is connected to the external load, and a support structure connected to the support frame. The support structure is axially movable relative to the support frame for moving the external load so as to aid in deploying the load or aid in controlling the center of gravity of the aircraft.
Further, in accordance with the present invention, a method for deploying and retrieving an external load from an aircraft broadly comprises the steps of providing a self contained modular deployment and retrieval system which includes a support frame, a winch connected to the support frame, and an axially movable support structure connected to the support frame for supporting a sheave, passing a tow cable on the winch over the sheave and connecting an end of the tow cable to the external load, and moving the support structure relative to the support frame from a retracted position to a deployed position so that the external load passes through an opening in the aircraft.
Other details of the modular integrated self contained cargo deployment and retrieval system of the present invention, as well as other objects and advantages attendant thereto, are set forth in the following detailed description and the accompanying drawings wherein like reference numerals depict like elements.